ASP .91 2 Stroke will not start

by Bob Fobian
(Union, MO)

It will not start, and I have no idea what the optimum needle settings are because I cannot find a manual

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Probably the low speed needle set too lean.
by: Michael from Oz

G'day

Try this.

Set the throttle so that it is about1/32 inch open (about the size of a pin diameter).

Open the main needle valve about three or four turns. This is not particularly critical at this point.

Attach some fuel tubing to the carby and blow into it. Can you hear air hissing into the carby? If not, the low speed needle (which needs a screw driver to adjust it and is opposite the main needle valve) is probably closed too far. As a first approximation, open it one turn then blow again. When you hear air through, then the LSN is at least open. Open it another half turn or so and see if she will start. From here you will have tune it is the usual way -

Go to full power.

Tune needle valve for peak revs

Go to best idle and adjust LSN for smooth running and good transition.

Repeat other two steps until happy.

But, keep the needle rich for a while (say about 10 flights) and use fuel with about 3 to 5% castor oil. ASP engines really need the castor to run in properly. Later you can omit the castor but I keep using it.

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WHAT IS THE LOW SPEED SETTING???
by: UNCLE GENE

WOW, SOMEONE THAT KNOWS WHAT HE IS TALKING ABOUT,
I HAVE BEEN USING STETHOSCOPES FOR TUNING CARBS FOR 50 YEARS.
IF YOU ARE AT THE FIELD AND DO NOT YOUR TOOLS YOU CAN DO A QUICK CHECK.
THROTTLE SET LOW FOR STARTING. PUT YOUR FINGER OVER THE CARB AND PULL THE PROP THRU...CHECK FOR FUEL IN THE LINE. IF NO FUEL, OPEN THE LOW NEEDLE ONE TURN OUT. PULL THE PROP THROUGH AND LOOK FOR FUEL. KEEP DOING THIS UNTIL YOU SEE FUEL FLOW. WHEN YOU SEE FUEL FLOW OPEN THE LOW NEEDLE A HALF TURN AND START THE ENGINE.

SAME AS ABOVE BUT A DIFFERENT WAY.
I DO THIS USUALLY WITH OTHER PEOPLES ENGINES AND THEY ARE AMAZED..:):)

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